Effect of Electric Field on Cation Migration and Electrode Reactions of Mortar with Different W/C Ratios

Abstract:

This study used Type I Portland cement with Na2Oeq of 0.67 % to fabricate a mortar specimen with a w/c ratio of 0.5 and a dimension of φ10 × 3 cm, adjusted to the 6 w/c ratios of 0.35, 0.40, 0.45, 0.50, 0.55 and 0.60. The specimen was applied constant current density of 9 A/m² during the Accelerated Lithium Migration Technique (ALMT) experiment. The results show that during the application of the current, over 86.4% of the electricity applied used in the production of gas through electrode reactions, and about 3.9-4.6% in cation migration. The required time of removal for Na+ and K+ decreased with increases in w/c ratio. The average removal percentage of Na⁺ and K⁺ increasing with the increase in w/c ratio. There was a good linear relationship between the ste^{Superscript textSuperscript text}ady-state flux and migration coefficient of Li⁺ and w/c ratio, and the steady flux of migration coefficient increase with increase in the w/c ratio.

• Periodical: Advanced Materials Research (Volumes 399-401)
• Pages: 1320-1325
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.399-401.1320
• Online since: November 2011
• Authors: Chih Chien Liu, Wen Ten Kuo, Shu Wang Hsu
• Keywords: Electrochemistry, ITZ, Lithium, Mortar

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